1. Field of the Invention
The present invention relates to an air conditioning structure for electrical appliances, such as power supply units for mixers, which have a housing containing one or more heat-generating electrical component parts.
2. Description of the Related Art
Electrical appliances, such as power supply units for mixers, or personal computers, incorporate various kinds of electrical component parts, such as a stabilized power supply unit and a CPU, and some of the electrical component parts cause large heat generation (each of which will be hereinafter referred to as a “heat-generating electrical component part”). Therefore, conventionally, air conditioning structures for electrical appliances are known in which a cooling fan is provided in a housing so as to cool heat-generating electrical component parts, as disclosed in Japanese Laid-Open Patent Publications (Kokai) No. 2003-271073 and No. 2003-76444.
Particularly, in Japanese Laid-Open Patent Publication No. 2003-76444, a cooling fan dedicated to a CPU is provided separately from a cooling fan for a power supply unit to thereby effectively cool the CPU generating heat.
However, cooling fans cause noise generation while performing the air-cooling function. For this reason, in electrical appliances of which quietness is demanded, it is important not only to cool each heat-generating electrical component part, but also to suppress noise generation by a cooling fan. For example, in a rack-mount power supply unit for mixers which processes recorded data of sound generated by a musical instrument or the like, suppression of leakage of noise to the outside, particularly forward of the mixer, is desired. Therefore, the conventional air conditioning structures remain to be improved in achieving a muffling effect in cooling the heat-generating electrical component parts contained in the housing.